Preheat the air fryer. Set it to 400°F (200°C) for 3–5 minutes. A preheated basket helps the tomatoes blister quickly.
Prep the tomatoes. Rinse and pat them dry.
Drying helps the oil and seasonings cling and prevents steaming.
Toss with oil and seasonings. In a bowl, combine tomatoes with olive oil, salt, pepper, and dried herbs. If using, add garlic and red pepper flakes. Stir gently to coat.
Arrange in the basket. Place tomatoes in a single layer in the air fryer basket or on a lined tray.
A little overlap is fine, but avoid piling them too high.
Air fry until blistered. Cook for 7–10 minutes, shaking the basket halfway. You’re looking for split skins and some browning, while the tomatoes still hold their shape.
Finish and season. Transfer to a bowl. If using, splash with balsamic vinegar and toss to coat.
Taste and adjust salt and pepper.
Serve warm or at room temperature. Garnish with fresh herbs. Use immediately or incorporate into another dish.